Bridge ramp



N. M. B-RYSON 2,452,289

Oct. 26, 1948.

BRIDGE RAMP 2 Sheets-Sheet 1 Filed April 2 1946 'INVENTOR.

Nan 0 M. Bryson BY y, I 1

Patented Oct. 26, 1948 BRIDGE RAMP Newall M.'-'Bryson, 'San Francisco,'6alif., assignor to Pallet Engineering Companw-San Francisco,

Application. April 2,v 1946,. Seria1TNOJ658973 Z GIaims. 1

This invention relatesto dock boardsandymore particularly, to improveddo ck'boards of thetype employed to span the gapi'betweenf spacedfplatforms, such, for example,as:theflocr of arailroad freight "car andan adjacent'loadin'g :dock.

"Iheprincipal obj ectzof the invention is to? provide 'an'improved dockboardithat is 'adapted to bridge gaps betweenplatforms 'dispose'd'in'many varied-relationships.

Another object of the inventionistoprovide a dock board that may besecurely anchored Jin place in anyof a variety of, positions withrespect to spacedplatforms defining a gap tobe bridged, whereby maximumloading efiiciency may be facilitated in cramped quarters at either-or.both ends of the dock board.

Another object of theinvention is to'provide a deck board that satisfiesthe" foregoingv objectives and-yet is simple to'manufacture andconvenient to use.

Another object ofthe'inventionis toprovlde a dock board that satisfiestheforegoin'g objectives and-yet, affords a high degree disafetyagainstthe usual hazards, such as running off one side of the ramp, skidding-onthe surfacethereof, "and jarring the dock board into aprecariousposition when approaching or leaving it incident totravel thereacross.

Anotherobject of the invention is to provide a dock board havinganimproved"mechanism for locking the dock board in position bridging a'gapbetween spaced platforms, irrespective "of a'lack ofuniformitydn t'hewidth of thegaporinthe elevations of 'the iplatforms along the oppositesides thereof.

Another obiect of the inventionis toprovide-a dock board that isspecially-adapted to easy handling-by one-man operating a conventionaldolly truck having an'elevator type ofloading" fork.

Still: further objectsand advantages o'fthe invention will:becomeapparent from the 'fol-lowing description .of a preferredembodimentthereof, taken :in conjunction with the accompanying drawings,inwhich:

Fig. .1 isa perspective view of *a dock board bridging the gap between.a loading platfor-m and the doorway of a railroadfreight car-a-"conventional dolly truck having an elevator type of -load" ing; forkbeing schematically shown in association therewith". to illustrate howthe deck 'board may beinstalled: in rposition I for use or 'removedwhenits useisno longer needed;

2-: issan.elevational-view of the dock board shown .in Fig.1,illustrating more clearly-'the-re'- lation' betweennthe dock board andthe two platforms connected thereby;

Fig, 3iisra plan view of the" dock board;

Fig. ii-is '-a-vertical sectional-view'ofthe-dock board, the plane ofthe section being indicated by the line 1-min; Figi3;

..for'increasingitsrigidity; I

#Alongits side e'dges,1.the ramp vl9.is provided,

Flgfifi. is an-explodedview of aportioncifxthe clampingmechanismemployedi'to lockithe dock board'in theypositionshowniniFigs.1ian'd"2.

Referringtothedrawings; aunts-board"! I "embddying :the present-invention is shown .in Fig.

1 :spanningtthe"gapbetweena loading dock 112 and the'fioor'l3tof a'freight car [4. A dollytiiuck |6,.*having anzelevator'type of loadingfork lLjis schematically shown in; position for' low'eringithe dock.board 'I l into place or I for removingi it, the dock board beingsuspended from the loadingfork I1 for thispurpose'bymeans offa chainl8,.orlthe like,1in amanner described in more detaill'here-f ber ofsmall .protuberances'. 2 I adapted ,tcim'part' antleski'd properties"thereto. The widthof the ramp 'l9incre'ases uniformly "from a minimum,

width at one end, somewhatiless .than thedoorway opening'in aconventional"freightcar, tona maximum width .atits opposite -.end,substa m. tiallyugre'ater'thanitsminimum width. There is thus provided awideentrance to the ramp. from the loading dock I 2, --whereby a dollytruckpn the loading platform 2 may ;approa'ch the ramp jfrom anydirection within a wi'de'horizontalangle. The

ramp 1' 9 is bent along a transversely extending line 22 thatpreferably. passes through the center ofv gravity thereof, so the-rampisibowed slight} upwardly. between its ends for. insuring "that they'end edges of 'theframpwill respectivelycontact the floor surface of the'dock'l2 and the '"tloor surface l 4 oft'he "freight car "I 6,irrespectiveof moderate differences intheir relative elevations.

.Theamount'of bending of the ramp'ior thisgpu i pose shouldrnot "be' sogreat, however, that too abrupta risefrom'either' loading surfacewillihe produced. In order to minimize theijarresultin'g from-wheels'rolling over the end .edgesofithe ramp, land "to. reduce thedanger Lthat i a person walkingoverthe ramp will' trip over'theendedg'esthereof, these edges are. preferably chanifered as shown ati 24 and 2 5.Reinforcinglbraces'ls ay be welded to the bottom surface or the ramp". I5

with complementary.side,;plates 2'1 .theLtQproject upwardly fromone endofthe ramp nearlyto the opposite endthe'reofand .serve aSiCUlbS or guiderails i to; prevent the wheels of .a; dolly. era-the, like from runningTover the side. edges of -the. ramp- The side plates .21 also assist(the .loraces 26 in strengthening theJramp l9. lThensideplates 2"!vinclude, portionstthat .depen'd loelowlv the rampdor s-a'portion of itslength fonengaging theedgeoflthe;

floor f4 defining one side of the gap to be bridged The adjustable dockengagin mechanisms re-,

spectively associated with the depending portions 28 of the side plates21 are identical exce t for being of opposite hand, and the followingdescription of one of them will be understood to apply to both. Eachdepending portion 23 is' provided with a longitudinally extending slot32 de-' fined by a straight lower edge 33 and by an upper edge that iscontoured to form a ratch '34 along a considerable portion of ,itslength. A dock engaging arm 36 is provided with a laterally projectingear or flange 31 atone end thereof that is adapted'to, bear against theside of the dock 12. At its opposite end, the arm 36 is pivotallymounted on the associated depending portion 28 of the side plate 21 bymeans of a short, flat, pivot bar 38 that may be integrally" formed withthe arm 36, as by welding. The pivot bar 36 projects laterally from thearm 36 through the adjacentslot 32' and terminates in a retaining disk39 that may be integrally formed with the pivot bar 38, as by welding.When the arm 36 is tilted upwardly about the pivot bar 38 with respectto the slot 32,

the pivot bar has its wide dimension parallel to' the slot, and it isfree to slide along the slot 32 in either direction from one end thereofto'the other. When the arm 36 is pivotally swung back to apositionparallel to the slot 32 the opposite side edges of the pivot barrespectively the lower edge 33 of the slot 32 and one of the teeth ofthe ratch 34 so as to lock the arm 36 against movement along the slot inone direction while still pennit ting movement of the arm along the slotin the oppositedirection'with only a slight upward tilt thereof as thepivot bar rides over the crest of each successive ratch" tooth. Theassembly is so arranged that the arm 36 is always free' to move towardthe wide end of the ramp and so that it may be locked in the mannerdescribed against movement toward the narrow end of the ramp, A bracket4| is welded or otherwise rigidly secured to each dependlngportio'n 28of the side platesz'lv tions 28 of the side plates 21 is brought intoabutment with the side edge of the platform l3, for example. The dockboard is then locked against accidental, horizontal, sliding movementmerely by 'moving both dock engaging arms, while they are supported ingenerally horizontally disposed positions by the brackets 4|,longitudinally in a direction to bring their respective cars 36 intoabutment with the'adjacent side edge of the otherplatform l2. Becausethe two pivot bars are oriented for engaging their respective ratches34, the dock engaging "arms are locked againstsubsequent longitudinalmovement in the opposite direction unless theyare manually tiltedupward- 1y for this purpose. The positions of the brackets 4i preventthe dock engaging arms 36 from tiltingdownwardly far enough for theengaged side of the platform I2 to prevent subsequent upward tilting ofthe arms for releasing the dock board. Two points of contact with theside edge of the platform 12 may always be efiected by the two dockengaging arms 36, and, depending upon whether or not the opposite sideedges of the two platforms l2 and [3 are parallel, either one or twopoints of contact with the side edge of the platform 13 will be effectedby one or both of the adjacent ends of the depending side plate portions28., In either case, the dock board will be positively anchoredagainst'accidental, longitudinal, sliding movement and againstaccidental, rotary, sliding movement about its vertical axis when itisjarred by transportingloads over the ramp 19 from one platform to theother.

Because the two dock engaging arms are independently adjustable, theopposite side edges of the two platforms may be disposed out of parallelto a very substantial degree without impairing the elfectiveness of themechanism for locking the dock board in place. Moreover, when it isdesired to approach or leave the ramp at a particularly secured to theupperedge of one of the side plates 21 in any suitable manner, as by ahook 42 on the chain passing through an aperture 43 in the side plate;and the opposite end of the chain may be passed through an aperture 44in the other side plate. To. permit ready adjustment of the amount ofslack in the chain (-8 between the two side plates while facilitatingeasy anchoring of the chain in the aperture 44, this aperture ispreferably formed with an upwardly projecting slot 46 communicatingtherewith, the width of the slot 56 being great enough to accommodate asingle, properly oriented link of the chain but through the aperture 44,and the link that is distween two platforms.

could be anchored with comparable effort and time by tying it with acommon knot, hitch, or

the like.

. When the chain I8 has been secured in place in the manner described,one man operating a dolly truck having an elevator type loadling forkmay lift the dock board from one location, transport it to anotherlocation, and set it down again in any desired position for bridging agap be- As illustrated in Fig. 1', this may be done merely by runningthe loading fork under the chain l8, elevating the loading fork, anddriving the dolly truck to the new locaby dropping the loading fork downagain. When.

the dock board H has once been positioned in this manner, the chain 18may be quickly pulled out of the aperture 44 in an obvious manner andthrown to one side to permit travel over the ramp l9. From the foregoingdescription of a preferred embodiment of the invention, it will beapparent that I have provided a dock board that is admirably adapted tobridge gaps between platforms disposed in many varied relationships andthat may be securely anchored in place while disposed for maximumloading efliciency. It will also be apparent that this has beenaccomplished by means of a structure that is simple and inexpensive tomanufacture and convenient to use under a wide variety of conditionswith a high degree of safety against the usual hazards, such as runningoff one side of the ramp, skidding on the surface thereof, or jarringthe dock board out of place when approaching or leaving it.

While I have disclosed a single preferred embodiment of the invent-ionin considerable detail, it is to be understood that this has been donefor illustrative purposes and that the invention is not limited to thedetails disclosed except as required by the appended claims.

I claim:

1. A dock board for bridging the gap between two spaced-apart platforms,comprising a ramp having a stop at one end to engage one of saidplatforms and a vertically depending plate portion adjacent each sideedge, said plate portion having a longitudinal slot therein, the upperedge of said slot having ratchet teeth therealong; and a slidablelocking bar, one end extending beyond said plate portion for engagingone of said platforms, and the opposite end of said locking bar havingan inclined locking member, the lower edge of said locking memberslidably supported on the lower edge of said slot and the upper edge ofsaid locking member selectively engaging said ratchet teeth.

2. A dock board for bridging the gap between two spaced-apart platforms,comprising a ramp having a stop at one end to engage one of saidplatforms and a vertically depending plate portion adjacent each sideedge, said plate portion having a longitudinal slot therein, onelongitudinal edge of said slot having ratchet teeth therealong; aslidable locking bar, one end extending beyond said plate portion forengaging one of said platforms, and the opposite end of said locking barhaving an inclined locking member, said locking member being adapted forsliding movement along said slot against the non-ratched edge thereofwhen said locking bar is in one rotative position and being adapted toselectively engage said ratchet teeth when said locking bar is in adifferent rotative position.

NEWALL M. BRYSON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 132,442 Clarke Oct. 22, 18721,131,783 Howard Mar. 16, 1915 1,144,836 Green June 29, 1915 1,178,661Martin Apr. 11, 1916 1,882,512 Lovejoy Oct. 11, 1932 2,284,022Schmeller, Sr May 26, 1942 2,337,138 Van Berg Dec. 21, 1943

